Shaft drive transmission failure - diagnosis

oldgit said:
yea ..all one or two of them :)
Click to expand...
I know the owner of the other one too ! A couple of years ago he gently nudged a submerged object later thought to be a tree trunk or branch which cracked the bellhousung and damaged the gearbox. Delicate things these shaft drive transmisduins if nudged in the wrong direction.
 
I serviced my shaft drives today, as the boat was lifted for a bum clean.
checked for play in the cutlass bearings - tiny bit
props all in good nick
gearbox oil crystal clear and in good health
stuffing box OK no adjustment required

time about 15 mins, parts used none
off to pub to invest the savings ;-)
 
kashurst said:
I serviced my shaft drives today, as the boat was lifted for a bum clean.
checked for play in the cutlass bearings - tiny bit
props all in good nick
gearbox oil crystal clear and in good health
stuffing box OK no adjustment required

time about 15 mins, parts used none
off to pub to invest the savings ;-)
Click to expand...

I wouldn't spend too much in the pub. I know the owner of a three year old shaft drive boat with less than 100 hours on that found himself with a bill for over £20k due to failed gearboxes. The boat was just out of warranty. Not saying it's common, but this, together with the odd other story told on here, leads me to believe that smugness should be avoided. It just might be you next.
 
CLB said:
I wouldn't spend too much in the pub. I know the owner of a three year old shaft drive boat with less than 100 hours on that found himself with a bill for over £20k due to failed gearboxes. The boat was just out of warranty. Not saying it's common, but this, together with the odd other story told on here, leads me to believe that smugness should be avoided. It just might be you next.
Click to expand...

Oh dont worry too much what he may have saved here he's paying in berthing fees for a bigger boat for the same space and a bigger engines and fuel bills to drive it. Tree, forest, you know the story :p
 
BruceK said:
Oh dont worry too much what he may have saved here he's paying in berthing fees for a bigger boat for the same space and a bigger engines and fuel bills to drive it. Tree, forest, you know the story :p
Click to expand...


Simply will not be in the pub long enough to spend any money, because he will be out actually boating. :)

Page one of the umpteen zillions weeny bits that dangle on the back of an o******* boat.
What could possibly go wrong.
The other 90% of the horrid thing available in 20 further diagrams on line. :)
XL-OMC-Cobra-transom-parts-1986-to1993.jpg

:)
 
oldgit said:
Simply will not be in the pub long enough to spend any money, because he will be out actually boating. :)

:)
Click to expand...


You only go out if you can see a full length reflection of yourself in the water. Maybe that's why you're having a period of grace....after a few oopsies earlier on.
 
CLB said:
Wonder how many more drawings make up this set?

View attachment 79261

:D
Click to expand...

KISS.
Err thats about it apart from a rather rugged length of 316 stainless steel, a great meaty lump of Phospher Bronze which will last a lifetime and a very chunky and strong prop.
None of the above mentioned having the "dissolve in water properties" of Aluminum and Rubber tubes * (*please change every two years or bye bye leg)
...ands lets not mention that Nemesis of all devils whisks......................a tiny weeny bit fishing line ...a few microns thick.
:):):).
 
Last edited:
oldgit said:
Simply will not be in the pub long enough to spend any money, because he will be out actually boating. :)
Click to expand...

This is the differentiator ^^^ .
Having started with outdrives and switching to straight shafts .
You can arrive at the boat knowing the risk of any stern gear problems and outdrive showstoppers are basically never need thinking thought about or saving for in VP dedicated war chest :)

Fuel is probably more but I knew that making the switch it’s the turn key ness that let’s face it supposed to be a leisure / hobby activity is more of a priority for me .

Aggregate costs if you toss in aged outdrive woes and general VP KAD repairs , in-spite of the greater fuel burn are the same .
Outdrive boat was 8/9 tons , shaft 17 tons dry so 19 with fluids.
So pro rata it’s cheaper .

Eg a Pershing 37 on shafts over 5/7 years would I reckon cost less to own than a outdrive S/Skr Porto35 ( 37 ft ) or FL T 37
With less if any unplanned downtime .

So Agree = more boating .
 
Portofino said:
This is the differentiator ^^^ .
Having started with outdrives and switching to straight shafts .
You can arrive at the boat knowing the risk of any stern gear problems and outdrive showstoppers are basically never need thinking thought about or saving for in VP dedicated war chest :)

Fuel is probably more but I knew that making the switch it’s the turn key ness that let’s face it supposed to be a leisure / hobby activity is more of a priority for me .

Aggregate costs if you toss in aged outdrive woes and general VP KAD repairs , in-spite of the greater fuel burn are the same .
Outdrive boat was 8/9 tons , shaft 17 tons dry so 19 with fluids.
So pro rata it’s cheaper .

Eg a Pershing 37 on shafts over 5/7 years would I reckon cost less to own than a outdrive S/Skr Porto35 ( 37 ft ) or FL T 37
With less if any unplanned downtime .

So Agree = more boating .
Click to expand...

Having been in the position to actually have an outdrive boat immediately followed by a shaft drive boat able to compare the two. regards that other much cherished myth fuel consumption.
Sold a Princess 33 with pair of VP 40A (130HP) on outdrives and then purchased a Broom 37 with a pair of
Perkins M130 with velvet drive gearboxes and shafts.Owned both boats for many years.
Fuel consumption per hour was virtually the same according to my carefully kept log.About 2,500 hours on the Princess and 1000 on the Broom.

Howver the out of action tale of woe and expence of the outdrives each season was a nightmare compared to the simple lift out, wash off A/F and back in joy of the shaft drive.
.......and no digging out those itty bitty little crustations from all the little nooks and crannies of the outdrives. :)

QED. :)
 
Last edited:
Pottering up a muddy creeks, ala Old Git, there may be little difference, but where I do my boating, I get almost double the mileage from my outdrive boat than I did with a previous shaft drive of a similar size. Last year my two week holiday alone, accounted for the best part of £2k saved in fuel.

I don't want to tempt fate, but in 20 years of outdrive boating, I have not had a single failure.

I will concede that annual maintenance is a pain, but I do it all myself so not at all costly, only a bit time consuming. Having said that, the hassle I have Seen in removing and replacing cutlass bearings doesn't make my bellows, anode and oil change seem all that bad.

Each to their own, but I have had, used and cruised with both, and the benefits of drives in decreased fuel consumption, better performance for HP, better shallow water capabilities, easier access to props for clearing fouling and the ability to dry out safely mean that drives win hands down.
 
what boat do you have now?
by the way I was just teasing before, I have had to replace a shaft drive gearbox on a targa 43 and a drive plate on a sealine T50 so I do know they can be buggers too.
 
CLB said:
Pottering up a muddy creeks, ala Old Git, there may be little difference, but where I do my boating, I get almost double the mileage from my outdrive boat than I did with a previous shaft drive of a similar size. Last year my two week holiday alone, accounted for the best part of £2k saved in fuel.

I don't want to tempt fate, but in 20 years of outdrive boating, I have not had a single failure.

I will concede that annual maintenance is a pain, but I do it all myself so not at all costly, only a bit time consuming. Having said that, the hassle I have Seen in removing and replacing cutlass bearings doesn't make my bellows, anode and oil change seem all that bad.

Each to their own, but I have had, used and cruised with both, and the benefits of drives in decreased fuel consumption, better performance for HP, better shallow water capabilities, easier access to props for clearing fouling and the ability to dry out safely mean that drives win hands down.
Click to expand...


Shaft cutlass bearing poss once every ten years perhaps more / £50.00. £50.00 per decade.No oil No anything else.

Outdrive rubberware every 2 years perhaps less, £ 200.00 ? £1000.00. per decade.
Plus oil/shaft seals/ fork seals//hydraulic hoses/lift rams/pumps etc etc.


Drying out no problem

Creek crawling mid Channel.
 
I didnt start this thread to spark off another outdrive vs shaftdrive debate.

I expect to have a further report on progress after the weekend. But it's not my boat so depends on others.
 
Blimey - how on earth was the ‘outdrives are doom’ beast awakened by a thread asking about shaft transmission failure?! :)
 
petem said:
Trash an outdrive and you can be back in the water in days. Trash a rudder or prop on a shaft drive boat and you can be out of the water for months waiting for a replacement to be cast.
Click to expand...

Or have your "P" bracket welded/straightened or your prop repaired at your local proper marine workshop (INVICTA MARINE Chatham Dockyard) and within 24 hours have it back on the boat.:)Sometimes same day repair if they are not busy and you ask very nicely.
All stone age basic stuff.
Rudder stocks/blades no problem.
Next Question :)
http://www.invicta-marine.com/Propeller/Contact.html
 
Last edited:
You must log in or register to reply here.

Share this page

Top